Can anybody check this for me.

Question

anonymous · Answer

Magnesium sulphate crystals $$(MgSO _{4}7H _{2}O)$$ can be dehydrated by heating. Calculate the percentage by mass of water present in the molecule.

anonymous · Answer

% composition of element=mass of element
                                         --------------* 100
                                         total mass

anonymous · Answer

% composition of element=18
                                        ---*100
                                        246
                                     
                                      =7.317073171

anonymous · Answer

is this right???

ipwnbunnies · Answer

Should be right. :)

kc_kennylau · Answer

You missed out the % sign in the answer I suppose